On Sun, 21 Jan 2001, Flip ter Biecht wrote:
> As we're all getting younger by the day, let me confirm that the problem
> with winmodems is that there's no comport in them. External modems use an
> existing comport and should be able to react to a valid signal sent through
> that comport. (It does however not mean that every external modem is hayes
> compatible...)
To expand... it's actually the UART chip which winmodems are
missing. (Universal Asynchronous Reciever Transmitter) This chip
sends signals *through* the serial port. It isn't a "comport"
itself.
An internal modem has its own UART onboard. An external modem
uses the UART on the motherboard which is associated with the
serial port in use, and of course a "winmodem" / "software modem" /
"modem emulator" simply has no UART at all.
Instead of using a hardware UART, it uses a software UART
emulator, which puts load on your CPU that should rightfully be
delegated a separate hardware UART. (Bill Gates refers to this
as "using excess CPU cycles"... as if IE is such a lightweight
app that it leaves the CPU sitting their idling... ehem)
Winmodems generally only ship the "drivers" for Windows, though
I have seen a winmodem or two with drivers for DOS included
(a few years back). I told my father that if the box says "UART
16550" on it, it's a real modem. He replied that the modem he
was looking at didn't say that, but it did say it would run DOS
programs. I then mistakenly told him that if it would run DOS
programs, it must certainly be a "real" modem. He bought it.
I was wrong. It was one of those rare winmodems with a DOS
driver. :-(
It would be *possible* for manufacturers to create a software
UART emulator (driver) for any OS. Of course, the whole reason for
winmodems is to reduce cost, and putting more effort into drivers
for little-used OS's would erode the winmodem profit margins... or
raise the price to the point that it would be cheaper to buy
a modem with a hardware UART.
> What, by the way are standard io addresses and irq values for internal pci
> modems? (I noticed a new help page in arachne 1.69 at
> file://doc\pcimodem.htm, which just gives an example with io d800 irq 10.
I *believe* that most PCI devices are plug'n'play. They may
have default values built-in, but I think they're set up by the
BIOS if the motherboard is PNP aware. Otherwise, set-up by
the PNP OS. Failing either of those, then you'll need some kind
of setup utility to write the desired values... anyway this is as
I recall it from trying to make a PNP sound card work on Linux and
DOS from some years back. The state of Linux pnp was still quite
rudimentary at the time.
In order to use sound, I was booting to DOS (pnp setup was
called from autoexec.bat IIRC), which wrote the desired values to
the card. Then I booted Linux using loadlin, and the values
written while in DOS remained intact.
> It took me months lately to find out the address of a pci ethernet card at
> 0x6100 irq 11 -or in fact redhat setup found it for me- and I'd be most
> happy with a more complete list of pci devices because the luxury of
> pentium, pci and pnp is still rather new in the recycling stores where I
> usually compose my systems)
In Linux, you can do '/sbin/lspci -v' to find out all kinds
of info on your PCI bus and the cards on it... but this will only
tell you one possible combination of several. I guess in many
instances that would be enough?
Here's the kind of stuff lspci will tell you:
00:09.0 Ethernet controller: Lite-On Communications Inc LNE100TX (rev 20)
Subsystem: Netgear FA310TX
Flags: bus master, medium devsel, latency 64, IRQ 11
I/O ports at e800
Memory at ea000000 (32-bit, non-prefetchable)
Expansion ROM at e9000000 [disabled]
So, if you're setting this up in DOS, you know at least e800
and IRQ11 are valid values.
> Apart from that, I found another nasty bit of hardware: a Compaq Qvision
> pci video card (1 mb, from 1996), that is autodetected nicely by win95, but
> not by Arachne.
Compaq has a reputation for "innovative design" or in the
words of the end user trying to figure it out, "deviating from
the standard."
The couple of Google links I looked at don't seem too promising:
http://www.xfree86.org/pipermail/newbie/2000-November/002479.html
http://support.microsoft.com/support/kb/articles/Q111/5/70.ASP
--
Steve Ackman [EMAIL PROTECTED]
Glass Host, Arts & Crafts http://www.delphi.com/crafts
Metamorphosis Glassworks Page http://twovoyagers.com/metamorphosis
